The present invention relates to a side-rail coupling for tarpaulin canopies of vehicle superstructures, in particular a coupling for length sections, which can be put together and separated, of upper side rails of canopy frames, which side rails have running and guide rails for a tarpaulin canopy which can be pushed together, the side rails having at least one hollow profile chamber and, connected to the latter, the running and guide rails serving for the supporting and guiding of rollers or roller carriages, which support bows carrying the roof tarpaulin, in a displaceable manner against the canopy frame, and adjacent length sections of side rails being connectable releasably to each other by means of coupling elements engaging in a form-locking manner in the hollow profile chamber of said side rails.
In the case of vehicles which are fitted with a tarpaulin canopy which is supported against the loading surface or the vehicle chassis by means of a canopy frame and can preferably be pushed together, in many cases there arises the necessity of being able to remove part of the canopy linkage in order to facilitate, or indeed to make possible, loading from above, or for loading with bulky goods. The parts of a canopy linkage which are to be removed for the above mentioned purposes are mainly length sections of the upper side rails thereof, which length sections have to be removed over a part of the length of the canopy frame in order to carry out a loading or unloading operation smoothly, and then have to be reinserted into the canopy linkage structure. The upper side rails of a canopy frame generally comprise a supporting profile, which is formed by at least one hollow profile chamber, and at least one running and guide rail, which is joined to said supporting profile, for supporting, preferably in a longitudinally displaceable manner, bows which carry a folding-top tarpaulin or at least a roof tarpaulin. Separable and removable adjacent length sections of the upper side rails of canopy frames or else of vehicle superstructures of different design are connected to each other in the conventional manner by means of rigid profile material sections which consist of solid material and engage in the hollow profile chambers of two side-rail sections to be coupled together, wherein the most varied means have been used in order to secure the mutual connection of two adjacent length sections of a side rail. Irrespective of the details of how the known means used for securing the coupling of two side-rail sections to be coupled together are obtained, they share the disadvantage of not being designed to engage automatically. Furthermore, the formation of the known coupling elements as solid material sections is associated with the disadvantage of a considerable weight.
The invention is based on an the object of providing a coupling for the individual length sections, connected releasably to one another, of the upper side rails of canopy frames, which coupling, completely irrespective of the construction of the side rail as a steel profile rail or as an extruded profile, is primarily distinguished by automatic engagement of the securing means and furthermore by having the lowest possible weight and also by being able to be produced and maneuvered in a simple manner.
According to the present invention, the present invention provides a side-rail coupling, where the fitting according to the invention of the coupling elements with bolt elements which automatically engage under spring loading ensures automatic securing of the coupling between two adjacent side-rail sections. Any risk of an accident resulting from possible negligence by the operator is therefore ruled out. Furthermore, the refinement according to the invention of a side-rail coupling has the additional advantage of being able to be separated relatively easily.
In a particularly preferred embodiment of a side-rail coupling it is additionally provided that the coupling elements are formed by length sections of a hollow profile material and are fitted with two bolt elements arranged opposite each other. This firstly ensures a considerable reduction in weight as compared to solid material parts and secondly ensures an additional improvement in the safety of the locking of the coupling elements to the side-rail sections to be coupled together. It is particularly advantageous here that the recesses assigned to the bolt elements are arranged in walls of the hollow profile chambers, which walls form outer circumferential walls of the side-rail profile, and pass through said walls, resulting in the advantage that during the intentional separation of the coupling of two adjacent side-rail sections, the bolt elements, irrespective of the manner of design of the side-rail sections as an extruded profile or as a steel profile, can be disengaged without the assistance of a tool and merely by hand. As a result, this leads to a considerable improvement in the handling of the canopy frame and therefore ultimately to a considerable increase in the quality of use of the canopy.
In one expedient individual refinement, as regards the fitting of the bolt elements and their loading springs into the coupling element, it is provided that two respective bolt elements which are arranged opposite each other are held in a sleeve-like guide aligned transversely to the longitudinal axis of the coupling element and are acted upon by a common compression spring which is arranged between them and is designed as a helical spring.
According to a further expedient individual refinement, as regards the fitting of the bolt elements and their loading springs into the coupling element, it can also be provided that two respective bolt elements which are arranged opposite each other are acted upon with a spring load in opposite directions by means of a common leaf spring, the leaf spring comprising a section bent in the shape of a U of spring steel sheet material and the two free ends of the legs of the leaf spring being supported against each other.
Regardless of the fact that the side-rail coupling according to the invention is eminently suitable for use in conjunction with every occurring form of design of side rails of canopy frames, a particularly preferred application is found by the side rail being composed of length sections of a steel profile, a hollow profile chamber which forms the supporting profile being formed by a region, deformed to form a square profile cross-sectional shape, of a unit comprising the supporting profile and integrally formed running and guide rail having a T-shaped cross-sectional profile, which unit is formed by folding a sheet-metal material or by deformation of a thin-walled hollow profile material.
Irrespective of the design of the side rail whose length sections are to be coupled to one another, it is finally also advantageous that the bolt elements which are arranged lying opposite each other of the coupling part are formed as push buttons which reach through mutually opposite walls of the supporting profile.